Crossover switching and pump system

ABSTRACT

The present invention involves several different embodiments related to a crossover switching valve. The crossover switching valve is preferably designed to receive fluid from a reservoir, or other fluid source, and direct the inflow and outflow of the fluid between the valve and one or more pumps. In one embodiment, the valve is configured to provide a substantially continuous flow rate when used in connection with a double acting pump. In another embodiment, the valve preferably includes an inflow port, an outflow port, and first and second ports configured to be fluidly connected to at least one pump. Another embodiment of the present invention is at least one conduit that preferably provides fluid communication between the first and second ports. Yet another embodiment is a fluid director that is preferably configured to alter flow of fluid through the conduit. Also disclosed is a pumping system that incorporates the crossover switching valve and a pump.

RELATED APPLICATIONS

The present application is a continuation-in-part application of U.S. application Ser. No. 11/103,272, filed Apr. 11, 2005, which claims benefit of U.S. Provisional Application No. 60/562,040, filed Apr. 14, 2004, both of which are hereby incorporated in their entirety by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to fluid valves and particularly to those capable of providing fluid direction control and switching functions at a substantially continuous rate.

2. Description of the Related Art

In order to enhance performance of their pumping systems, many manufacturers have replaced single acting pumps with double acting pumps. These reciprocating pumps typically utilize one or more cylinders together with appropriate valves for controlling fluid flow to and from the cylinders. The pumps are configured to simultaneously pump fluid from one cylinder while drawing fluid into another cylinder. When the fluid of the pumping cylinder is expended, the pump switches the pumping action to the other cylinder, while supplying the expended cylinder with fluid. This reciprocating action permits the pump to have a relatively continuous flow.

The double acting pumps may be connected to a rotating crossover valve that switches the fluid flow by rotating a cylindrical fluid director to communicate with various ports on the pump. These crossover valves, however, are required to operate under low to medium pressure in most applications but also very high pressures in many applications. For example, some applications may require pressures in excess of 3,000 psi. Additionally, many of the fluids that are being pumped in such applications contain coarse particles, which can cause significant wear and tear on the valve leading to valve leakage and failure.

The rotating crossover valves have several problems when operating under such conditions. For example, one problem is that the coarse particles are often drawn into an area between the rotating fluid director and stationary valve housing and wear the fluid director and housing. As a result, the rotatable crossover valves are unable to operate for long periods of time and frequently require replacement, typically of the entire crossover valve.

SUMMARY OF THE INVENTION

There is need for a valve that can operate without the disadvantages of the rotatable crossover valves. Specifically, there is a need for a valve that can operate with various fluids under high or low pressure with increased longevity. Additionally, there is a need for a valve that can operate with fluids containing particles of the size that would provide texture in paint without producing significant wear on the valve.

The present invention involves several different embodiments related to a crossover switching valve. The crossover switching valve is preferably designed to receive fluid from a reservoir and moderate the inflow and outflow of the fluid between the valve and the pump. The valve is preferably configured to provide a substantially continuous flow rate when used in connection with a double acting pump. Such a valve is disclosed herein and in U.S. patent application Ser. No. 11/103,272, filed Apr. 11, 2005, which is hereby incorporated by reference in its entirety and made a part of this specification. The valve is configured to permit pumping of fluids that contain particles of the size that provide texture in paint without creating significant wear on the valve. In some embodiments, it is contemplated that the valves disclosed herein can operate with fluids containing particles that are smaller and larger than those that provide texture in paint.

In one embodiment of the present invention, a valve is provided that is configured to provide substantially continuous flow, fluid direction control, and switching functions. The valve preferably includes an inflow port that is configured to permit fluid to flow into the valve from a fluid reservoir and an outflow port that is configured to discharge fluid from the valve. The valve may also preferably include a first port that is configured to be in fluid communication with a first portion of a dual acting pump and a second port that is configured to be in fluid communication with a second portion of the dual acting pump. The valve preferably includes an internal conduit that is configured to provide fluid communication between the inflow port, the outflow port, the first port, and the second port. Also preferably included are first and second occluders, the first and second occluders are preferably configured to have first and second positions. The valve also preferably includes first and second actuators, the first actuator is preferably configured to linearly translate the first occluder between the first and second positions, and the second actuator is preferably configured to linearly translate the second occluder between the first and second positions. In operation, the valve is preferably configured such that when the first and second occluders are in the first position, the inflow port is preferably in fluid communication with the first portion of the dual acting pump, and the outflow port is preferably in fluid communication with the second portion of the dual acting pump. The valve is also preferably configured such that when the first and second occluders are in the second position, the inflow port is preferably in fluid communication with the second portion of the dual acting pump, and the outflow port is in fluid communication with the first portion of the dual acting pump.

In another embodiment, a continuous flow valve is provided that preferably includes an inflow port that is preferably configured to connect to a reservoir and an outflow port that is preferably configured to discharge fluid from the valve. The valve may preferably include first and second ports that are preferably configured to be in fluid communication with at least one pump. The valve also preferably includes a conduit that interconnects the inflow port, the outflow port, the first port, and the second port. The valve may also preferably include an occluder configured to have a first and second position. When the occluder is in the first position, the occluder is preferably configured to separate the conduit into a first configuration consisting of two portions. The first portion preferably permits fluid communication between the inflow port and the first port, and the second portion preferably permits fluid communication between the outflow port and the second port. In the second position, the occluder is preferably configured to separate the conduit into a second configuration of two portions. The first portion of the second configuration preferably permits fluid communication between the inflow port and the second port, and the second portion of the second set preferably permits fluid communication between the outflow port and the first port.

In yet another embodiment, the valve may include a flow director that is configured to direct fluid flow between the inflow and first port and between the outflow and second port in one position. In another position, the flow director may be configured to direct fluid flow between the inflow and second port and between the outflow and first port. In other embodiments, a system is provided in which the valve is connected to a pump.

Also disclosed herein is a pumping system that comprises a pump and a crossover switching valve integral with or directly coupled to said pump. Also disclosed is a system that can include a pump housing; and a crossover switching valve integral with or directly coupled to said pump housing. In another embodiment, the system can include a pump housing and a crossover switching valve positioned within or adjacent to said pump housing.

In another embodiment, a system configured to provide continuous flow of a fluid therefrom is provided. The can include a double acting pump and a crossover switching valve. The crossover switching valve can include a cylinder chamber configured for operation of a plurality of pistons therein and a plurality of passageways within the valve that permit fluid to be provided to the double acting pump and that permit fluid to be received from the double acting pump so as to provide a steady flow of fluid from an outflow port of the system. The crossover switching valve can be integral with the double acting pump.

A valve is provided that is configured to provide continuous flow of a fluid. The valve can include a cylinder chamber that is configured for operation of a plurality of pistons therein and a plurality of passageways within the valve that permit fluid to be provided to a pump and that permit fluid to be received from the pump so as to provide a steady flow of fluid from an outflow port.

For purposes of summarizing the invention, certain embodiments, advantages, and novel features of the invention have been described herein. Of course, it is to be understood that not necessarily all such embodiments, advantages, or features are required in any particular embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the present invention, which are believed to be novel, are set forth with particularity in the claims. The invention, together with further objects and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, in the figures of which like referenced numerals identify the like elements, and wherein:

FIG. 1 is a schematic view of a crossover switching valve connected to a pumping system including a fluid reservoir, a pump, and an outflow line, the flow of the fluid and direction of the pump are shown by arrows.

FIG. 2 is a schematic view of a crossover switching valve connected to a pumping system, the flow of fluid and direction of the pump are shown by arrows.

FIG. 3 is a cross-sectional view of one embodiment of the crossover switching valve.

FIG. 4A is a cross-sectional view of a seat against which an occluder may be engaged.

FIG. 4B is a top view of the seat of FIG. 4A.

FIG. 5A is a top view of a spacer with bleed holes shown in dashed lines that extend from a bore in the middle of the spacer to an exterior side of the spacer.

FIG. 5B is a side view of the spacer of FIG. 5A, a bleed hole and the middle bore of FIG. 5A shown in dashed lines.

FIG. 6A is a cross-sectional view of a cylinder in accordance with one embodiment.

FIG. 6B is a top view of a cylinder in accordance with one embodiment, a bore is shown in dashed lines that extends from an exterior portion of the cylinder to within the cylinder.

FIG. 7 is a perspective view of one embodiment of a crossover switching system that integrates a pump and a crossover switching valve.

FIG. 8 is a partial transparent view that illustrates portions of the crossover switching system of FIG. 7.

FIG. 9 is a cross-section view of the crossover switching system of FIG. 7.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a schematic drawing of a pumping system in which a crossover switching valve 30 is used. The crossover switching valve 30 is preferably in fluid communication with a fluid reservoir 32 by an inflow line 34, one example of which would be tubing. The inflow line 34 is preferably coupled to the crossover switching valve 30 by an inflow port 36. The crossover switching valve 30 includes a first pump port 38 and a second pump port 40. The first pump port 38 is preferably in fluid communication with a top pump cylinder 42 of a double acting pump 44 by a first pump line 46. One example of a double acting pump 44 is provided in U.S. Pat. No. 6,398,514 to Smith et al., the entirety of which is incorporated herein by reference. The second pump port 40 is preferably in fluid communication with a bottom pump cylinder 48 by a second pump line 50.

The crossover switching valve 30 also preferably includes an outflow port 52 that is coupled to an outflow line 54. The inflow port 36, first pump port 38, second pump port 40, and outflow port 52 are preferably fluidly connected by an internal conduit 56. The continuous flow valve 30 preferably includes a base 55, a top 57, an inflow portion 59, and an outflow portion 61. The designations top, base, inflow, or outflow, etc. are used herein only for descriptive purposes and are not intended to indicate any particular orientation or configuration of the continuous flow valve 30.

Preferably, the crossover switching valve 30 also includes an inflow occluder 58 and outflow occluder 60, as shown in FIG. 1. The inflow occluder 58 is preferably coupled to a first end of a rod 62. A piston 64 is preferably coupled to the second end of the rod 62, the piston 64 being housed within a first cylinder 66. Preferably, movement of the piston 64 within the first cylinder 66 translates through the rod 62 to movement of the inflow occluder 58 within the internal conduit 56.

A similar configuration is illustrated with respect to the outflow occluder 60 in FIG. 1. The outflow occluder 60 may be coupled to a first end of a rod 68, and a second end of the rod 68 may be coupled to a piston 70. The piston 70 is movable within a second cylinder 72 such that movement of the piston 70 is translated through rod 68 to movement of the outflow occluder 60 within the internal conduit 56. When the piston 64, 70 rises to the top of the cylinder 66, 72, the respective occluder 58, 60 preferably engages a top seat 74, as is shown with respect to the inflow occluder 58 of FIG. 1. When a piston 64, 70 is lowered to the bottom of the cylinder 66, 72, the respective occluder 58, 60 preferably engages a bottom seat 76, as is shown with respect to the outflow occluder 60 of FIG. 1.

With continued reference to FIG. 1, the occluders 58, 60 preferably have a generally spherical shape. While the occluders 58, 60 are illustrated as spheres, they may consist of several other shapes. For example, the occluders 58, 60 may be conical, ovoid, etc. Other shapes for the occluders 58, 60 may also be used.

The occluders 58, 60 may be made from any number of materials. Preferably, the occluders 58, 60 are made of stainless steel. The occluders 58, 60 may also include a hardened surface, e.g., made of tungsten carbide, hard chrome, etc. The occluders 58, 60 may also be made of other materials such as other carbon steels, ceramics, and plastics, for example. The occluders 58, 60 may be threadably connectable to the rod 62, 68 by having an internal threaded bore that couples with a threaded first end of the rod 62, 68. Other ways of coupling the occluders 58, 60 to the rod 62, 68 may also be used. For example, the occluders 58, 60 may be integrally formed with the rod 62, 68, bonded to the rod 62, 68, etc.

In one embodiment, the occluders 58, 60 are substantially a spherical shape with a diameter of about 0.625 inches. In other embodiments, the diameter of the occluders 58, 60 may vary from about 0.4 inches to 0.8 inches. In yet other embodiments, the diameter of the occluders 58, 60 may be substantially greater than about 0.8 inches and less than about 0.4 inches.

The seats 74, 76 preferably have a cylindrical shape with a hollowed portion 75 to permit passage of fluid and the rod 62 therethrough, as shown in FIGS. 4A and 4B. The hollowed portion 75 within the cylinder of the seat 74, 76 preferably includes a portion 77 that is angled axially outward such that the diameter of the hollowed portion 75 increases along a longitudinal axis X of the seat 74, 76. In one embodiment, the seat 74, 76 generally comprises a cylindrical shape, and the axis X is defined by the axis of the cylinder. Thus, the angled portion 77 is preferably configured to accommodate the occluder such that sealing of the passageway through the seats 74, 76 may occur. The seats 74, 76 also preferably include a step 79 that is configured to secure the seats 74, 76 in place when assembled. Other ways of securing the seats 74, 76 may also be used.

While they are illustrated as cylindrical, the seats 74, 76 may be constructed in any shape that will accommodate the occluder and provide sealing of the passageway. Additionally, although the surface of the angled portion 77 illustrated is substantially straight, the surface of the angled portion 77 may be convex, concave, or other shapes. The seats 74, 76 are preferably machined from polyethylene, although they may be formed in other ways and consist of other materials. For example, the seats 74, 76 could be injection molded, cast, formed, etc., and the seats 74, 76 may be made from other plastics, metals, composites, etc.

The hollowed portion 75 of the seats 74, 76 is preferably about 0.5 inches in diameter. In other embodiments, the hollowed center may range from about 0.3 to about 0.7 inches in diameter. In yet further embodiments, the hollowed portion 75 may be significantly greater than about 0.7 inches or less than about 0.3 inches in diameter.

In some embodiments, the occluders 58, 60 and the seats 74, 76 may be configured in the valve 30 such that replacement thereof requires minimal time and expense. For example, in one embodiment, the occluders 58, 60 may be threadingly coupled to the rods 62, 68 such that replacement thereof may be easily made upon disassembly. In some embodiments, other means of coupling may be used to facilitate timely and inexpensive replacement. In some embodiment, the seats 74, 76 may also be configured to be easily replaced upon disassembly of the valve 30.

The double acting pump may operate in two stages. During the first stage, a carriage 78 of the double acting pump 44 moves down as indicated by the arrow Y. While the carriage 78 is moving down, fluid may be supplied to the top pump cylinders 42. While FIG. 1 appears to show one top cylinder 42, in the illustrated embodiment, another cylinder 42 is located behind the one shown. Hence, the pump may have one or more top pump cylinders 42 and one or more bottom pump cylinders 48. While the carriage 78 is moving down, fluid may be pumped from the bottom pump cylinders 48 through the second line 50. During this stage, the inflow occluder 58 engages the seat 74 while the outflow occluder 60 engages the seat 76. Thus, fluid supplied to the inflow port 36 is directed to the first pump port 38. This fluid is then supplied to the top pump cylinder 42 through the first pump line 46. In this same configuration, fluid is pumped from the bottom pump cylinder 48 through the second pump line 50 and into the second pump port 40. Upon entering the second pump port 40, the fluid is directed through the outflow port 52 to the outflow line 54.

In a second stage of the operation of the pump 44, the carriage 78 of the double acting pump 44 is moving up, as indicated in FIG. 2 by the arrow Z. During this stage, fluid is pumped from the top pump cylinder 42 to the first pump port 38, and fluid is supplied to the bottom pump cylinders 48 through the second pump port 40. Preferably, the piston 64 is shown at or near the bottom of the first cylinder 66 such that the inflow occluder 58 engages the bottom seat 76. In this configuration, the occluder 58 and the seat 76 seal the connection between the inflow port 36 and the first pump port 38 and permit fluid communication between the inflow port 36 and the second pump port 40. In this embodiment, the piston 70 is preferably at or near the top of the second cylinder 72 such that the outflow occluder 60 engages the top seat 74. Accordingly, the occluder 60 and the seat 74 seal the connection between the outflow port 52 and the second pump port 40 and permit fluid communication between the outflow port 52 and the first pump port 38.

In one embodiment, and as illustrated in FIG. 2, fluid supplied into the inflow port 36 is directed through the internal conduit 56 to the second pump port 40. The fluid is transferred to the bottom pump cylinder 48 through the second pump line 50. Fluid from the top pump cylinder 42 is supplied to the first pump port 38 by the first pump line 46. Upon entering the first pump port 38, the fluid is directed through the internal conduit 56 to the outflow port 52 and is thereupon discharged through the outflow line 54.

The outflow line 54 may be directly connected to the output instrument (not shown), if desired. In some embodiments, it may be desirable to combine the outflow line 54 of multiple valves 30, such as may be the case in supplying a resin and catalyst, for example. In these embodiments, the outflow line 54 of the various valves 30 may be connected to a manifold (not shown) that combines the output of the valves 30. The manifold preferably may combine the fluids and direct the fluids through a tube that provides stationary mixers, such that the fluids may be mixed into a homogenous blend. Upon leaving the tube, the homogenous fluid may be supplied to an output instrument.

While FIGS. 1 and 2 show different embodiments of the crossover switching valve 30, it will be readily apparent to one of ordinary skill in the art that alternative configurations may be used to accomplish the same objectives. For example, the first pump port 38 and the first pump line 46 may be coupled with the bottom pump cylinders 48 instead of the top cylinder 42, and the second pump port 40 and the second pump line 50 may be coupled to the top cylinder 42 instead of the bottom pump cylinder 48. Additionally, the embodiments shown in the Figures show the top pump section having one cylinder set behind another cylinder while the bottom pump section is shown in the illustrated embodiments of the Figures as having two cylinders set apart. However, one or more cylinders may be used in the double acting pump 44, and the cylinders 42, 48 may have various configurations. For example, the top and bottom pump sections of the double acting pump may have one cylinder, two cylinders, three cylinders, etc. Further details about one exemplary pump that may be used are found in U.S. Pat. No. 6,398,514 to Smith et al., previously incorporated by reference. In other embodiments, the valve 30 may have multiple pump ports 38, 40 and multiple pump lines 46, 50. In further embodiments, the valve 30 may be connected to various pumps.

The double acting pump 44 is preferably configured to supply a substantially continuous flow rate through the first pump line 46 and second pump line 50 by its reciprocating action. The double acting pump 44 and its computer controller preferably control actuation of the pistons 64, 68 of the crossover switching valve 30. In a preferred embodiment, a servo motor (not shown) of the double acting pump 44 may be connected to an air compressor (also not shown) that controls the pressure difference across the pistons 64, 68. In another embodiment, a linear transducer 67 may control the signal. The orientation of the pistons 64, 68 may also be changed by air solenoid valves, electronic solenoids, hydraulics, mechanics or other means that are apparent to those of ordinary skill in the art. The orientation of the pistons 64, 68 preferably switches with the change in direction of the carriage 78 of the double acting pump 44 to provide a continuous flow rate through the valve 30.

The crossover switching valve 30 may consist of four general segments: a top 57 inflow 59 portion, a base 55 inflow 59 portion, a top 57 outflow 61 portion, and a base 55 outflow 61 portion. The top 57 inflow 59 portion may include a top inflow section 80, an inflow section 82, and an intermediate inflow section 84. Likewise, the top 57 outflow 61 portion may include a top outflow section 86, an outflow section 88, and an intermediate outflow section 90. The base 55 inflow 59 portion may comprise an inflow portion spacer 92 and an inflow portion cylinder 94. The base 55 outflow 61 portion may include an outflow portion spacer 96 and an outflow portion cylinder 98. The top inflow section 80, inflow section 82, intermediate inflow section 84, top outflow section 86, outflow section 88, and intermediate outflow section 90 preferably include bores or passageways that are configured to provide fluid communication therethrough and create the internal conduit 56. The various portions, their features, and operations will be described below.

In some embodiments, portions of the valve 30 may be combined in the manufacturing process. For example, although the Figures illustrate embodiments in which the top 57 inflow 59 portion is made of three discrete sections, two or more of these sections may be combined such that the top 57 inflow 59 portion is constructed of only one or two pieces. In yet other embodiments, the portions of the valve 30 may include other sections than those previously identified.

The various portions of the crossover switching valve 30 are preferably machined from aluminum or other appropriate metals. The various portions of the flow valve may also be made from other materials such as ceramics and plastics, for example. In some embodiments, the portions of the valve may be formed, cast, molded or other appropriate manufacturing methods may be used.

As shown in FIG. 3, the inflow section 82 and the outflow section 88 are preferably positioned between their respective top section 80, 86 and intermediate section 84, 90. As shown in FIG. 3, a passageway 100 that is substantially axially aligned with the rod 62 preferably extends from the top of the inflow section 82 to its base. The inflow port 36 preferably extends from an exterior of the inflow section 82 to the passageway 100, providing fluid communication between the inflow port 36 and the passageway 100. In one embodiment, the connection of the inflow port 36 and passageway 100 may form a T-shaped conduit, as shown in FIG. 3, with respect to the inflow section 82.

The passageway 100 preferably has a diameter sufficient to accommodate the inflow occluder 58 such that the inflow occluder 58 is moveable within the passageway 100. The inflow occluder 58 is preferably positioned so that it may engage the top seat 74 and the bottom seat 76 within the passageway 100.

In one embodiment, the passageway 100 may have a diameter of about 0.688 inches. In other embodiments, the passageway 100 may have a diameter between about 0.4 inches to about 0.8 inches. In yet other embodiments, the passageway 100 may have a diameter substantially less than about 0.4 inches and greater than about 0.8 inches.

In one embodiment, the inflow port 36 may have a diameter of about 0.5 inches. In other embodiments, the inflow port 36 may have a diameter between about 0.3 inches and about 0.8 inches. In yet other embodiments, the inflow port 36 may have a diameter substantially less than about 0.3 inches and greater than about 0.8 inches.

The passageway 100 may have a bore on the top and bottom side configured to accommodate placement of the seats 74, 76 therein, engaging the step 79 of the seats 74, 76. In one embodiment, the bores may have a diameter of about 0.876 inches. In other embodiments, the bores may have a diameter between about 0.5 inches and about one inch. In yet other embodiments, the bores may have a diameter that is substantially greater than about one inch and less that about 0.5 inches.

With continued reference to FIG. 3, the outflow section 88 may have a similar configuration as the inflow section 82. Preferably, a passageway 102 extends from the top to the base side of the outflow section 88 that is substantially axially aligned with the rod 68. The passageway 102 is also preferably configured to accommodate a top seat 74 and a bottom seat 76 such that the outflow occluder 60 may engage either seat 74, 76 and is moveable between the two seats 74, 76. The passageway 102 preferably has a diameter sufficient to accommodate the outflow occluder 60 such that the outflow occluder 60 is moveable within the passageway 102.

The outflow port 52 preferably extends from an exterior of the outflow section 88 to the passageway 102, providing fluid communication between the exterior side and the bore. The outflow port 52 is preferably configured to permit coupling with an outflow line 54. In one embodiment, the outflow port 52 and respective passageway 102 may form a T-shaped conduit, similar to one embodiment of the inflow portion 82. In one embodiment, the outflow section 88 may be sized with similar dimensions and features as the inflow section 82 as described above.

As illustrated in FIG. 3, in one embodiment, the inflow section 82 and the outflow section 88 are separate pieces from the respective top sections 80, 86 and intermediate sections 84, 90. In this embodiment, the sections 82, 88 may be configured to be rotatable about the axis of the respective rod 62, 68. This may permit various orientations of the inflow and outflow ports 36, 52 and may permit interchangeability between the sections 82, 88. In some embodiments, the exterior portion of the sections 82, 88 may provide etchings or markings that correlate with the appropriate alignment and orientation desired. For example, if the sections 82, 88 are configured to be interchangeable, an exterior side of the sections 82, 88 may be marked for a desired alignment with the top and intermediate sections 80, 84 on the inflow portion 59. A different side of the sections 82, 88 may be marked for a desired alignment with the top and intermediate sections 86, 90 on the outflow portion 61.

The top inflow section 80 and top outflow section 86 are both preferably configured with a passageway extending from the base that is connectable to the respective passageway 100, 102 extending through the inflow section 82 and outflow section 88. The passageway in the top inflow section 80 is preferably shaped to direct fluid flow toward the top outflow portion 86. As shown in FIG. 3, the passageway may form a right angle, a circular arch, or other means to direct fluid towards the outflow portion 61.

The passageway within the top outflow section 86 preferably includes a passageway that is configured to receive the fluid from the top inflow section 80 and direct the fluid towards the passageway of the outflow section 88. This passageway may comprise a right angle as shown in FIG. 3, a circular arch, or other means that may appropriately direct the fluid flow. In the illustrated embodiment of FIG. 3, a top coupler 106 may be provided to connect the passageways of the top inflow section 80 and the top outflow section 86.

In some embodiments, the top inflow section 80 and the top outflow section 86 may be directly connected or formed together such that a top coupler 106 is not necessary. In one embodiment, the passageways of the top sections 80, 88 have a diameter of about 0.5 inches. In other embodiments, the diameter may be between about 0.3 inches and about 0.8 inches. In yet other embodiments, the diameter may be substantially less than about 0.3 inches and greater than about 0.8 inches.

Continuing reference to FIG. 3, the top outflow section 86 preferably includes the second pump port 40. The second pump port 40 may comprise a bore extending from an exterior side of the section 86 that fluidly communicates with the passageway of the top outflow section 86. The second pump port 40 may have a diameter that is about 0.5 inches in one embodiment. In other embodiments, the second pump port 40 diameter may be between about 0.3 inches and about 0.8 inches. In yet other embodiments, the second pump port 40 may have a diameter that is substantially less than about 0.3 inches and greater than about 0.8 inches.

While FIGS. 1-3 illustrate the second pump port 40 as being located on the top outflow section 88, the second pump port 40 may be located elsewhere between the two occluders 58, 60. For example, the second pump port 40 may be located on the top inflow section 80 or the on the top coupler 106.

The intermediate inflow section 88 preferably includes a passageway 104 that is configured to fluidly communicate with the passageway 100 of the inflow section 82. The passageway 104 of intermediate inflow section 84 is preferably configured to direct fluid from the inflow section 82 toward the intermediate outflow section 90. As shown in FIG. 3, the passageway 104 of the intermediate inflow section 84 may be configured at a right angle, a circular arch, or by other means that will direct the fluid flow toward the intermediate outflow section 90. In some embodiments, the passageway 104 may be substantially the same size as that of the passageways of the top sections 80, 86, having the same dimensions. In other embodiments, the passageway 104 may be a different size that that of the top section 80, 86 passageways.

The passageway 104 of the intermediate inflow section 84 also preferably fluidly communicates with the first pump port 38. The first pump port 38 is preferably configured to provide fluid communication between the exterior of the intermediate inflow section 84 and the internal conduit 56.

The intermediate outflow section 90 is preferably configured with a passageway 105 that fluidly communicates with the passageway 102 of the outflow section 88. The passageway 105 of the intermediate outflow section 90 is preferably configured to receive fluid from the intermediate inflow section 84 and direct the fluid to the outflow section 88. This may be accomplished by the passageway 105 being configured in a right angle as shown in FIG. 3, by a circular arch, or by other means that will direct the fluid flow. A base coupler 112 may be provided to fluidly connect the passageways 104, 105 of the intermediate inflow section 84 and the intermediate outflow section 90. In some embodiments, the intermediate inflow section 84 and the intermediate outflow section 90 may be directly connected or formed together such that the bottom coupler 112 is not necessary.

While FIG. 3 illustrates the first pump port 38 located on the intermediate inflow section 84, one of ordinary skill in the art will appreciate that the first pump port 38 may be placed at any location between the two occluders 58, 60. For example, as illustrated, the first pump port 38 may be located on the intermediate flow section 84, or the first pump port 38 may be located on the intermediate outflow section 90 or the base coupler 112.

The intermediate inflow section 84 preferably includes an aperture 114 on the base of the section 84 that is substantially the same diameter as the rod 62 and is axially aligned therewith, as illustrated in FIG. 3. The aperture 114 preferably extends from the base of the intermediate inflow section 84 to the internal conduit 56. This aperture 114 is configured to receive the rod 62 therethrough. The aperture 114 also preferably is configured to accommodate a primary seal 116 that prevents leakage of fluid within the internal conduit 56.

In one embodiment, the aperture 114 may have a diameter of about 0.39 inches. In other embodiments, the aperture 114 may have a diameter between about 0.3 inches and about 0.7 inches. In yet other embodiments, the aperture 114 may have a diameter significantly less than about 0.3 inches and greater than about 0.7 inches.

The intermediate outflow section 90 also preferably includes an aperture 114 that extends from the base of the section 90 to the internal conduit 56. The aperture 114 is preferably substantially the same diameter as the rod 68 and is axially aligned therewith. The aperture 114 is preferably configured to accommodate the rod 68 and a primary seal 116 that prevents leakage from the internal conduit 56. The aperture 114 of the intermediate outflow section 90 may have substantially the same diameter as that of the aperture 114 of the intermediate inflow section 84. In other embodiments, the aperture 114 of the intermediate outflow section 90 may have a different diameter than that of the intermediate inflow section 84.

The inflow portion spacer 92 also preferably has an opening 118 that aligns with the aperture 114 to accommodate the rod 62 extending therethrough. The opening 118 preferably accommodates a secondary seal 120 that prevents leakage from entering within the inflow portion cylinder 94 in the event that fluid leaks through the primary seal 116.

The outflow portion spacer 96 also preferably includes an opening 118 that is configured to align with the aperture 114 of the intermediate outflow section 90 to accommodate the rod 68 extending therethrough. The opening 118 is preferably configured to accommodate a secondary seal 120 to prevent fluid from entering into the outflow portion cylinder 98 in the event that fluid leaks past the primary seal 116.

The opening 118 through the inflow and outflow portion spacers 92, 96 may have a diameter of about 0.39 inches. In some embodiments, the diameter may be between about 0.3 inches and about 0.7 inches. In other embodiments, the diameter may be significantly less than about 0.3 inches and greater than about 0.7 inches. In some embodiments, the diameter of the inflow and outflow portion spacer 92, 96 opening 118 may be the same. In other embodiments, the diameter may differ between the inflow and outflow portion spacers 92, 96.

As shown in FIGS. 5A and 5B, at least one channel 122 is preferably located in the inflow and outflow portion spacers 92, 96 between the location providing for the primary seal 116 and the secondary seal 120. The channel 122 preferably extends from the opening 118 to an exterior portion of the valve. The channel 122 is preferably configured to permit fluid to flow from the opening 118 to the exterior surface in the event that fluid penetrates the primary seal 116. Fluid flowing through the channel 122 will provide a visual indication that the primary seal 116 requires replacement. Preferably, the channel 122 is provided on both the inflow portion 59 and the outflow portion 61 with respect to the corresponding rod 62, 68. As shown in FIGS. 5A and 5B, the inflow and outflow portion spacers 92, 96 may include more than one channel 122.

As shown in FIGS. 6A and 6B, the inflow portion cylinder 94 preferably includes an inflow cylinder chamber 124 and a base opening 126. The base opening 126 is configured to accommodate a base cylinder cover 128 that seals the inflow cylinder chamber 124. The inflow cylinder chamber 124 is preferably configured to accommodate the inflow portion piston 64.

In one embodiment, the inflow cylinder chamber 124 may have a diameter of about 2.993 inches. In some embodiments, the inflow cylinder chamber 124 may have a diameter between about one inch and about five inches. In other embodiments, the inflow cylinder chamber 124 may have a diameter significantly less than about one inch and greater than about five inches. The inflow cylinder chamber 124 preferably has a length that provides space in the event of wear.

In the event that the occluders 58, 60 or the seats 74, 76 deteriorate, the pistons 64, 70 may have a greater stroke length. To accommodate for this, the cylinder chamber 124 may provide space on either side of the pistons 64, 70 when in a minimum or maximum configuration. Such space will prevent the pistons 64, 70 from striking the top of the cylinder chamber 124 or the base cylinder cover 128. In one embodiment, about one inch may be provided on either side of the pistons' 64, 70 minimum or maximum configuration. In some embodiments, between about 0.5 inches and about 2 inches may be provided. In other embodiments, the space may be substantially less than about 0.5 inches or greater than about 2 inches.

With reference to FIG. 3, in one embodiment, the inflow portion piston 64 may have a diameter of about 2.980 inches. In some embodiments, the inflow portion piston 64 may have a diameter between about one inch and about five inches. In other embodiments, the inflow portion piston 64 may have a diameter that is significantly less than about one inch and greater than about five inches.

The pistons 64, 70 are configured to be movably displaced within the cylinders 94, 98. The pistons 64, 70 may comprise a channel 134 about the pistons' 64, 70 perimeter that permits placement of a piston seal 133 therein to prevent leakage of air between the cylinder chamber 124, 136 above the piston 64, 70 and below the piston 64, 70.

The pistons 64, 70 may be threadably attached to the respective rods 62, 68. While this may be accomplished in a number of ways, in one embodiment, a bolt may be threaded through an opening extending through the pistons 64, 70 such that it threadably engages a threaded bore at the end of the pistons 64, 70. Other methods of attachment may also be used to couple the pistons 64, 70 to the rods 62, 68.

Returning reference to FIGS. 6A and 6B, the inflow portion cylinder 94 preferably includes an opening 130 that extends from the top of the inflow portion cylinder 94 to the inflow cylinder chamber 124. The opening 130 is preferably sized and configured to permit placement of the rod 62 therethrough, and to accommodate placement therein of a rod bearing 131 (shown in FIG. 3). In one embodiment, the opening 130 may also accommodate the secondary seal 120 (also shown in FIG. 3).

The opening 130 may have a diameter of about 0.39 inches in one embodiment. In some embodiments, the opening 130 may have a diameter between about 0.3 inches to about 0.7 inches. In other embodiments, the opening 130 may have a diameter that is substantially less than about 0.3 inches and greater than about 0.7 inches.

In some embodiments, a bore 133 may extend along the opening 130 for placement therein of a rod bearing 131. In one embodiment, this bore 133 may have a diameter of about 0.5 inches. In some embodiments, the bore 133 may have a diameter of between about 0.3 inches and about 0.7 inches. In other embodiments, the bore 133 may have a diameter that is substantially less than about 0.3 inches and greater than about 0.7 inches.

As illustrated in FIGS. 6A and 6B, in one embodiment, the cylinders 94, 98 may include a passageway 138 that extends from the exterior of the cylinder to the cylinder chambers 124, 136. Preferably, passageway 138 provides fluid communication between the exterior of the cylinders 94, 98 and the cylinder chambers 124, 136 to permit introduction or evacuation of air, for example, therethrough.

The passageway 138 may have a diameter of about 0.125 inches in one embodiment. In some embodiments, the passageway 138 may have a diameter between about 0.1 inch and about 0.3 inches. In other embodiments, the passageway 138 may have a diameter that is substantially greater than about 0.3 inches and less than about 0.1 inches.

Passageway 138 is preferably configured to be connectable to an air compressor (not shown) or other fluid or gas regulator that will actuate the pistons 64, 70 according to the pump 44 position. When the carriage 78 of the pump 44 is moving down, fluid or gas is drawn into the top pump cylinder 42 through the first pump line 46 and is pumped out of the bottom pump cylinders 48 through the second pump line 50.

As shown in FIG. 1, while the carriage 78 is moving down, the servo motor or linear transducer 67 preferably directs the air compressor or other fluid or gas regulator to evacuate the inflow cylinder chamber 124 above the inflow portion piston 64, drawing the inflow portion piston 64 toward the top of the chamber 124. In this configuration, the inflow portion piston 64 moves the inflow occluder 58 to engage the top seat 74 and seals the conduit 56 connecting the inflow port 36 and the second pump port 40. This configuration permits the fluid to flow from the inflow port 36 to the first pump port 38 and through the first pump line 46 to the top pump cylinders 42.

Also while the carriage 78 of the pump 44 is moving down, the servo motor or linear transducer 67 preferably directs the air compressor or other fluid or gas regulator to pressurize the outflow cylinder chamber 136 above the outflow portion piston 70, moving the outflow portion piston 70 toward the base of the cylinder chamber 136. In this configuration, the outflow portion piston 70 moves the outflow occluder 60 to engage the bottom seat 76 and seals the conduit 56 connecting the outflow port 52 and the first pump port 38. This configuration permits fluid to flow from the bottom pump cylinders 48 to the outflow port 52 through the second pump line 50 and the second pump port 40.

When the carriage 78 reaches a predetermined or desired point in its downward stroke, the pump 44 reverses the movement of the carriage 78. When direction of the carriage 78 is reversed, flow in the first and second pump lines 46, 50 is also reversed. In this configuration, fluid is pumped from the top pump cylinder 42 through the first pump line 46, and fluid is supplied to the bottom pump cylinders 48 through the second pump line 50, as shown in FIG. 2.

Upon switching the direction of the carriage 78, the servo motor or linear transducer 67 preferably directs the air compressor or other fluid or gas regulator to pressurize the inflow cylinder chamber 124 above the inflow portion piston 64, moving the inflow portion piston 64 toward the base of the cylinder chamber 124. In this configuration, the inflow portion piston 64 moves the inflow occluder 58 to engage the bottom seat 76 and seals the conduit 56 connecting the inflow port 36 and the first pump port 38. Upon movement of the inflow occluder 58 toward the bottom seat 76, fluid communication between the inflow port 36 and the second pump port 40 is preferably permitted, as shown in FIG. 2. This configuration permits fluid entering the inflow port 36 to be directed to the second pump port 40. The fluid is thereupon supplied to the bottom pump cylinders 48 through the second pump line 50.

When the carriage 78 is moving downward, the servo motor or linear transducer 67 also preferably directs the air compressor or other fluid or gas regulator to evacuate the outflow cylinder chamber 136 above the outflow portion piston 70, moving the outflow portion piston 70 toward the top of the outflow cylinder chamber 136. In this configuration, the outflow portion piston 70 causes the outflow occluder 60 to engage the top seat 74 and seals the conduit 56 connecting the outflow port 52 and the second pump port 40. Upon movement of the outflow occluder 60 toward the top seat 74, fluid communication is provided between the outflow port 52 and the first pump port 38, as shown in FIG. 2. This configuration permits fluid to be pumped from the top pump cylinder 42 to the first pump port 38 through the first pump line 46. Upon entering the first pump port 38, the fluid is directed through the conduit 56 to the outflow port 52.

In one embodiment, the gas used to actuate the pistons 64, 70 may be air. However, various gases may be used in place of air for the purposes herein. In other embodiments, fluids may also be used. In yet further embodiments, the pistons 64, 70 may be actuated by other means. For example, the pistons 64, 70 may be operated by electromagnets or other electric or electromechanical means.

Threaded bolt bores 140 (FIG. 3) are preferably provided to accommodate bolts, by which the various sections of the valve 30 are secured. Other ways of assembling the valve 30 may also be used. Between each section of the valve 30, there are preferably cylindrical channels 142, as shown in FIGS. 5A and 5B, that may permit placement therein of an o-ring to seal the internal conduit 56 and cylinder chambers 124, 136 from leaking fluid.

Preferably, the connections between the inflow line 34 and the inflow port 36 and between the outflow port 52 and the outflow line 54 are sealed to prevent leakage of fluid. The crossover switching valve 30 preferably includes sealing between each of the connections, portions, and sections to prevent leaking of the fluid within the valve. Many means may be used to accomplish the sealing, as are readily apparent to those of skill in the art. An o-ring placed in a channel between such connections is one example of how the sealing may be accomplished.

The crossover switching valve 30 described above can be used with a number of pumps. For example, it may be used with a reciprocating pump referred to as a “rod pump.” Rod pumps find use in high precision or fluid metering applications. Rod pumps utilize a fluid cylinder having a closed end bore within which a pump rod is moved. The open end of the fluid cylinder bore supports a pressure seal against the pump rod for maintaining pressure within the cylinder bore. As the pump rod is drawn from the cylinder bore, low pressure or “draw” is created in the cylinder bore allowing fluid flow into the cylinder. Conversely, as the pump rod is driven into the cylinder bore the fluid is pressurized. Combinations of check valves can be used to control fluid flow to and from the pump.

Rotary pumps can also be used and are characterized as having a shaft coupled to a source of rotary power which is supported within a pump body. The pump body defines a chamber or cavity within which a fluid movement or displacement device is rotated by the input power shaft. One type of rotary pump is an impeller type pump. In such pumps, a rotor is positioned within the pump chamber and rotated by the input power shaft. The rotor in turn supports a plurality of blades which are sized and configured in correspondence with the interior chamber of the pump housing. An input port and an output port can be formed in the pump housing in communication with the chamber. As the input drive shaft rotates the rotor and its plurality of impeller blades within the pump chamber, the fluid can be drawn into the chamber through the input port and forced outwardly through the output port.

Another type of rotary pump is a turban or vane-type pump. The turban or vane pump can utilize a housing defining a chamber which is usually cylindrical in shape which supports a plurality of static vanes radially disposed within the chamber interior. An armature can be rotatably supported within the pump chamber and further supports a plurality of rotating vanes which are moveable with respect to the static vanes. A drive shaft is preferably coupled to a source of operative rotary power and is further coupled to the armature. As rotary power is applied to the armature, the interaction of the rotating vanes and static vanes produces a turban-like displacement of the fluid within the chamber. An input port can be coupled to one end of the chamber while an output port can be coupled to the downstream end of the pump chamber.

Still another type of rotary action pump is a “peristaltic pump,” which may be referred to as a “hose pump.” Peristaltic pumps can utilize a housing within which a generally cylindrical chamber is formed. A flexible tubing or hose can be positioned against the outer surface of the housing chamber. One end of the tubing or hose can be coupled to an input fluid supply while the remaining end forms an output port for the pump. A rotor is rotatably supported within the chamber and further supports one or more rollers about its periphery. The rollers are positioned against the flexible tubing or hose and are of sufficient size to deform the hose to provide pinching or closure at the point of roller pressure. A drive shaft is coupled to the rotor and to a source of rotational power. As the rotor rotates, the rollers displace quantities of fluid in the direction of rotor rotation to transfer the fluid from the input source to the output port.

While several pumps can be used in applications which require the pumps to run for relatively long periods at a steady state, in certain environments pumps can also be capable of providing short term small volume runs to transfer fluid in more precise quantities. For example, some of these pumps are “fluid metering” pumps and are characterized by precise volume delivery of fluid. In many instances, fluid metering pumps can be used in an operative environment in which the rotating member is moved through small angular displacements substantially less than a full rotation.

The crossover switching valve 30 disclosed above can also be used with a double-acting rod pump that includes a frame support, a carriage slidably movable upon the frame support in first and opposed directions, and a plurality of rod pump sections coupled to the carriage and the frame support. The pump can also include a pump screw rotatably supported by the support frame, a bi-directional motor for rotating the pump screw in first and second rotational directions, and engagement means on the carriage for engaging the pump screw such that first and second rotational direction rotation of the pump screw moves the carriage in opposed first and second direction movement. Such engagement means can be a plurality of mechanical gears or other devices that are used to convey mechanical movement. The pump can also include a valve coupled to the rod pump sections for controlling fluid flow to and from the first and second rod pump sections.

FIGS. 7-9 illustrate a combined pump and crossover valve system 230 which incorporates a crossover valve 231 similar conceptually to the previously described crossover valve 30 of FIG. 1. The new crossover valve is incorporated into a double-acting pump 244 and advantageously uses a single fluid or gas chamber to change the valve seating. In the illustrated figures, the valve is disposed between a portion of first and second pump cylinders 242, 248. The pump 244 includes a pump housing 201 that encompasses the cylinders 242, 248 and the integrated crossover valve 231. The pump housing 201 advantageously includes parts of the cylinders 242, 248 and the valve as portions of its perimeter and is preferably disposed toward one end of the crossover switching system 230. The crossover valve 231 is preferably integral with, directly coupled to, contained within, and/or adjacent to the pump housing 201. The crossover valve 231 includes an inflow port 236 and an outflow port 252. The fluid being pumped is received by the inflow port 236 and is discharged from the outflow port 252. The valve operates to control a series of passageways contained within the pump to regulate the fluid being pumped during the reciprocating action of the pumping cylinders 242, 248.

FIG. 8 is a partial transparent view to illustrate various working components of the pumping system. As illustrated in the figure, the double-acting pump 244 can include a transmission gear 202 that is configured to receive input drive from a bi-directional motor. The first gear is mechanically coupled with a first gear 204 and a second gear 206. The first gear 204 is mechanically coupled with a first ball screw 208 that preferably extends between the first gear 204 and the first pump cylinder 242. Similarly, the second gear 206 is mechanically coupled with a second ball screw 210 that preferably extends between the second gear 204 and the second pump cylinder 248. The ball screws 208, 210 preferably include a thread along its exterior that extends a portion of the length of the screws 208, 210.

The double acting pump 244 also preferably has a plurality of ball screw nuts 212, 214. The ball nuts 212, 214 include an internal bore in which threads or ball bearings reside to meshingly engage the corresponding threads of the ball screws 208, 210. The ball screw nuts 212, 214 are preferably disposed on the ball screws 208, 210 and are preferably in a fixed rotational arrangement. They may be fixed in any number of ways. For example, as illustrated in FIG. 8, a plurality of rods 216 are disposed adjacent the ball screws 208, 210 and the ball screw nuts 212, 214. The rods 216 extend through apertures in the ball screw nuts 212, 214 to limit rotation of the nuts when the ball screws 208, 210 rotate. Accordingly, when the ball screws 208, 210 rotate, the ball screw nuts 212, 214 are axially moved upward or downward along the corresponding ball screw depending upon the arrangement of the threads and the rotational direction of the ball screw.

Each ball screw nut 212, 214 is preferably coupled to a piston 218, 220. The pistons 218, 220 are slidingly received within the first and second pump cylinders 242, 248. The pistons 218, 220 are configured to move axially with the nuts 212, 214 as the ball screws 208, 210 are rotated. As the pistons 218, 220 axially move upward with respect to the corresponding cylinders 242, 248, the cylinder is filled with the fluid that is being pumped through inlets in the cylinder walls, and as the pistons 218, 220 move downward and into the corresponding cylinders 242, 248, the fluid is pressurized and discharged from the cylinder through outlets in the cylinder walls. The inlets and outlets in the cylinder are in fluid communication with the crossover switching valve 231 and preferably receive and discharge the fluid through the valve 231.

The pistons are preferably configured in alternating arrangements. For example, when the first piston 218 is descending into the first pump cylinder 242, the second piston 220 is being withdrawn from the second pump cylinder 248. Thus, when the fluid in the first pump cylinder 242 is being discharged, the second pump cylinder 248 is being filled with fluid. There is preferably an annular space between the pistons 218, 220 and the corresponding cylinders 242, 248 to permit fluid to be drawn in from the inlet. The pistons 218, 220 are preferably also configured to switch directions are about the same time. Accordingly, when the first piston 218 switches from descending into the first pump cylinder 242 to being withdrawn from the first pump cylinder 242, the second piston 220 switches from being withdrawn from the second pump cylinder 248 to descending into the first pump cylinder 248. Accordingly, there is a substantial continuity in the flow of fluid from the fluid reservoir into the valve 231 and a substantial continuity of flow being discharged from the valve 231.

Although the motor that operates the double acting pump 244 has been described as a bi-directional motor, other motors coupled with alternative gearing arrangements could be used to accomplish the same function. For example, a single directional motor could be used with a series of clutches that operate to engage and disengage a series of gearing arrangements that may also achieve bi-directional rotation. Additionally, while FIG. 8 illustrates a pump having only two operating pistons, it is possible to arrange the pump to have more or less operating pistons while accomplishing the same function. For example, the pump may have three or four pistons.

With reference to FIG. 9, a cross-sectional view of one embodiment of the crossover switching system 230 is illustrated. In this embodiment, the crossover switching valve 231 is disposed between the cylinders of the illustrated double acting pump 244. The valve 231 includes features that are similar to embodiments of the valve disclosed above and is configured to achieve the same function of regulating the pumping fluid.

The crossover switching valve 231 preferably includes a first chamber 222 into which fluid is received through the inflow port 236 from the fluid reservoir. An occluder is disposed within the first chamber 224 to control to direction of flow through the first chamber 224, similar to the occluders previously discussed. The occluder is axially movable within the first chamber between at least a first and second position. In either position, the occluder is preferably configured to engage a seat that is placed in cylindrical channels 203 similar to the seats described above with respect to the crossover valve. A rod is coupled to the occluder and translates movement of a first piston 264 to the occluder between positions. The first chamber 224 is preferably axially aligned with the movement of the occluder to accommodate axial positioning of the occluder within the first chamber 224.

The first chamber 224 is in fluid communication with a first passageway 238, which is in direct fluid communication with the first pump cylinder 242, and a second passageway 240, which is in direct fluid communication with the second pump cylinder 248. When the occluder is in one position, it seals the first passageway 238 such that fluid is prevented from entering into the first pump cylinder 242 through the first passageway 238. While the occluder is in this position, fluid is directed from the inflow port 236, into the first chamber 222, through the second passageway 240, and into the second pump cylinder 248. The occluder is preferably in this configuration when the second piston 220 is being withdrawn from the second pump cylinder 248, thereby permitting the second pump cylinder 248 to be filled with fluid.

When the pistons 218, 220 change direction, the valve's 30 first piston 264 preferably moves the occluder to a second position in which the occluder seals the second passageway 240 leading to the second pump cylinder 248. As the occluder moves from the first position to the second position, the first passageway is unsealed and is permitted to be in fluid communication with the inflow port 236. Accordingly, as the first piston 218 is being withdrawn from the first pump cylinder 242, the first pump cylinder 242 is permitted to receive fluid through the first chamber 222 and first passageway 238 to fill the cylinder 242. Thus, the occluder directs fluid that enters the valve 231 to the cylinder 242, 248 which is being filled at that time in the pump's cycle.

In a second portion of the valve 231, the valve includes a second chamber 224 that is in fluid communication with a third passageway 246, which is in turn in direct fluid communication with the first pump cylinder 242, a fourth passageway 250, which is in direct fluid communication with the second pump cylinder 248, and the outflow port 252. As previously described, the valve includes a second piston 270 that actuates an occluder disposed within the second chamber 224 between at least two positions. In one position, the occluder seals the third passageway 246 while permitting the second chamber 224 to be in fluid communication direct fluid communication with the outflow port 252 and the fourth passageway 250. The occluder is preferably in this position when the second piston 220 is descending into the second pump cylinder 248. As the piston 220 descends, the fluid within the second pump cylinder 248 is pressurized and discharged through the fourth passageway 250. The fluid travels from the fourth passageway 250, through the second chamber 224, and out the outflow port 252. Similar to the first chamber 224, the second chamber 224 is preferably configured to be aligned with the axial movement of the occluder.

When the pistons 218, 220 switch direction, the occluder is preferably moved to another position in which the fourth passageway 250 is sealed, but fluid communication is provided between the first pump cylinder 242 and the outflow port 252 through the third passageway 246 and the second chamber 224. This arrangement permits the fluid that is pressurized in the first pump cylinder 242 to be discharged through the outflow port 252 when the first piston 218 is descending into the first pump cylinder 242.

The cycles of the pump and the valve are preferably coordinated such that fluid is permitted to be received through the first passageway 238 at about the same time that fluid is permitted to be discharged through the fourth passageway 250. Likewise, fluid is permitted to be received through the second passageway 240 at about the same time that fluid is permitted to be discharged through the third passageway 246. Accordingly, when the pistons are being withdrawn from the corresponding cylinders, the cylinders are filled with fluid, and when the pistons are descending into the corresponding cylinders, the fluid is discharged through the passageways and from the outflow port 252.

Although the valve 231 is discussed above and shown in the figures as being located between two pump cylinders, it will be appreciated that the valve 231 can be located in other configurations and orientations with respect to the pump. Also, although the inflow port 236 and outflow port 252 are identified with respect to the first and second chambers 222, 224, it will be appreciated that the inflow port 236 can operate as the port from which the fluid is discharged from the valve 231 and the outflow port 252 can operate as the port into which the fluid is provided into the valve 231. If the ports are used for such an alternative operation, the occluder positions are merely reversed to provide the appropriate flow to and from the pump cylinders.

The valve also preferably includes a cylinder chamber 324 in which the first and second pistons 264, 270 are located. In one embodiment, as illustrated in FIG. 9, the cylinder chamber 324 is positioned between the first and second chambers 222, 224, so as to permit reciprocating movement of the first and second piston 264, 270 within the same cylinder chamber 324. In one embodiment, the pistons 264, 270 are configured to have an offsetting and/or opposite cycle. In such an arrangement, the pistons 264, 270 are configured to permit fluctuation between a position in which the pistons 264, 270 are located at a maximum distance from each other and a position in which the pistons 264, 270 are located at a minimum distance from each other. For example, as illustrated in FIG. 9, the pistons 264, 270 are in a configuration in which they at a maximum distance from each other. The pistons 264, 270 will assume this position when the fluid or gas within the cylinder chamber 324 and between the pistons 264, 270 is pressurized. The pistons 264, 270 assume a position in which they are a minimum distance from each other when the fluid or gas within the cylinder chamber 324 and between the pistons 264, 270 is evacuated, thus drawing the pistons 264, 270 together.

The valve rods, like those shown in valve 30, are preferably connected to the piston and set up so that when fluid in the chamber 324 is pressurized, it moves the pistons 264, 270 away from each other. This action moves the occluders to engage the top seat of the first chamber 222 and the bottom seat of the second chamber 224. This arrangement allows for fluid to be drawn into cylinder 242 and the fluid in cylinder 248 to be pumped out. When the fluid in the chamber 324 is evacuated, the pistons 264, 270 move close together. This action moved the occluders to engage the bottom seat of the first chamber 222 and the top seat of the second chamber 224. This arrangement allows for fluid to be drawn into cylinder 248 and the fluid in cylinder 242 to be pumped out.

Actuation of the pistons is similar to that previously described. However, with the embodiment illustrated in FIGS. 7-9, only one actuating fluid port 326 is used because there is only one cylinder chamber 324. While additional ports 326 can be provided to the cylinder chamber 324, the use of one port 326 may reduce manufacturing costs and simplify the construction and operation of the valve 231. The actuating fluid port 326 is preferably in fluid communication to the interior of the cylinder chamber 324 for injecting fluid or gas into the chamber 324 or evacuating the fluid or gas from the chamber 324. In the illustrated embodiment, the port 326 preferably communicates to the center of the cylinder chamber 324 such that the path of the pistons 264, 270 do not cross the fluid port 326. In other embodiments, there may be multiple actuating fluid ports 326 on either side of the pistons 264, 270.

The orientation of the first and second chambers 222, 224 are preferably along the same axis as that of the pistons 264, 270. Thus, actuation of the pistons permits axial movement of the respective occluder within the first and second chambers 222, 224. In one embodiment, the axis of the first and second chambers 222, 224 are also parallel to the axis of the first and second pump cylinders 242, 248.

The embodiments of the crossover switching system 230 illustrated in FIGS. 7-9 provide several advantages flowing from the fact that the pump and the crossover valve are combined into a single unit. One advantage is the incorporation of connections between the pump and the valve within the system. Additionally, each of the connections between the pump and the valve provide fluid in a single direction.

Another advantage is the size of the system. Because the valve is integrated into, coupled directly with, or contained within the housing of the pump, the size of the system can be made more compact, which allows for ready transportation or storage. Furthermore, with one cylinder chamber 324 and reciprocating and offsetting pistons 264, 270, the system is significantly balanced during operation.

Although this crossover switching valves 30, 231 and system 230 have been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the valves 30, 231 and system 230 extend beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and obvious modifications and equivalents thereof. In addition, while a number of variations of the valves 30, 231 and system 230 have been shown and described in detail, other modifications will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or subcombinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the disclosure. Accordingly, it should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the disclosed valves 30, 231 and system 230. Thus, it is intended that the scope of the disclosure herein provided should not be limited by the particular disclosed embodiments described above. 

1. A pumping system comprising: a pump; and a crossover switching valve integral with, positioned within, or directly coupled to said pump.
 2. A pumping system configured to provide continuous flow of a fluid therefrom, the system comprising: a double acting pump; and a crossover switching valve comprising: a first passageway and a second passageway configured to receive fluid from a fluid reservoir and a third passageway and a fourth passageway in direct fluid communication with an outlet; a plurality of pistons operably coupled to a plurality of occluders, the occluders being movable between at least a first position in which the occluders limit fluid flow through the first passageway and third passageway and a second position in which the occluders limit fluid flow through the second passageway and fourth passageway.
 3. The pumping system of claim 3, wherein the plurality of pistons are positioned within a single cylinder chamber.
 4. The pumping system of claim 3, wherein the crossover switching valve is integral with the double acting pump.
 5. A valve configured to provide continuous flow of a fluid comprising: a cylinder chamber configured for operation of a plurality of pistons therein; and a plurality of passageways within the valve that permit fluid to be provided to a pump and that permit fluid to be received from the pump so as to provide a steady flow of fluid from an outflow port.
 6. A pumping system configured to provide continuous flow of a pumping fluid therefrom, the system comprising: a double acting pump having first and second pumping chambers and first and second pistons one operable in each chamber; a crossover switching valve in fluid communication with each of said chambers to supply pumping fluid to said first chamber and eject pumping fluid simultaneously from said second pumping chamber in a first mode and then in the second mode to reverse these operations; and wherein movement of the valve from one mode to another is accomplished by alternately providing positive pressure and negative pressure to a single chamber, which operates two separate matable valve seats.
 7. The pumping system of claim 6 wherein the pumping fluid is paint.
 8. The pumping system of claim 6 wherein the pumping fluid is a material that includes particles of a size such that they can provide texture to a painted surface. 